NCT02404155

Brief Summary

Clozapine (CLZ) is the most effective antipsychotic for treatment-refractory schizophrenia (SZ). Despite the overwhelming evidence of superior efficacy, CLZ is infrequently prescribed in the US, at a considerably lower rate than the estimated prevalence of treatment-resistant SZ, especially for African-Americans (AA). Recent evidence suggests that low Absolute Neutrophil Counts (ANC), either at baseline or during treatment are a significant barrier to CLZ use in AA patients in the US, where guidelines mandate CLZ discontinuation if ANC drops below 1500 cells/mm3. The investigators group has found that discontinuation of CLZ in AA patients is over twice that in European-American (EA) patients (N\~400; 42% vs.19%, P=0.041) and initiation rates are 50% lower. In a Statewide study (N=1875), the investigators reported that discontinuation was more frequently due to neutropenia in the AA sample, though no AA had developed agranulocytosis (8 cases in EA). Benign Ethnic Neutropenia (BEN) in people of African ancestry, including AAs, identifies a group (50% of AA) with low ANCs but no increased risk of agranulocytosis or infection. Low baseline or in-treatment fluctuations requiring CLZ discontinuation under current prescribing guidelines are common in CLZ-treated persons with BEN. In the investigators recent pilot study of N=12 AA patients with BEN, treatment was safely and successfully continued with CLZ despite low baseline ANC (outside current guidelines). Recent evidence implicates a polymorphism in the Duffy Antigen Receptor Chemokine (DARC) gene in the pathophysiology of BEN. In homozygotes (FY-/-) for the DARC null allele, mean within-subject neutrophil counts are reduced, resulting in sporadic ANC \<1500 cells/mm3 in 10-15% of people with the allele. In population studies, the FY-/- genotype is found in 0.01% of EAs, 99.3% of sub-Saharan Africans (SSA), and 68% of AAs. Further, a missense DARC mutation has been reported to interact with the DARC FY-/- in determining low WBC in AAs. Normal patterns of week-to-week fluctuation in ANC levels in individuals of African ancestry with BEN and the DARC null genotype are not known, and no published research has examined variation in ANC in African ancestry CLZ-treated SZ patients with BEN and the DARC null genotype (FY-/-). Such data are also lacking on individuals with BEN without the DARC null genotype. Conducting such research will generate genetic marker and safety data that could be used to expand access to CLZ for AA patients who otherwise are eligible to receive this superior treatment option.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
274

participants targeted

Target at P75+ for not_applicable schizophrenia

Timeline
Completed

Started Jul 2015

Longer than P75 for not_applicable schizophrenia

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

February 26, 2015

Completed
1 month until next milestone

First Posted

Study publicly available on registry

March 31, 2015

Completed
3 months until next milestone

Study Start

First participant enrolled

July 1, 2015

Completed
6.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

October 26, 2021

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

October 26, 2021

Completed
1.3 years until next milestone

Results Posted

Study results publicly available

January 31, 2023

Completed
Last Updated

January 31, 2023

Status Verified

January 1, 2023

Enrollment Period

6.3 years

First QC Date

February 26, 2015

Results QC Date

November 2, 2022

Last Update Submit

January 11, 2023

Conditions

Outcome Measures

Primary Outcomes (2)

  • Change in White Blood Cell (WBC) (mm3) and Absolute Neutrophil Counts (ANC) (mm3) in Persons According to Presence of the DARC Null Allele.

    24 week period baseline and endpoint

  • Number of Episodes of Agranulocytosis (Count).

    6 months

Study Arms (1)

Clozapine

EXPERIMENTAL
Drug: Clozapine

Interventions

Clozapine

Eligibility Criteria

Age18 Years - 64 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may qualify if:

  • Eligible and recommended for clozapine treatment (e.g. treatment resistant schizophrenia, schizoaffective disorder, bipolar disorder, other psychotic disorder, delusional disorder, hostility, other documented rationale)
  • Male or Female
  • African Ancestry (African, African-American or African-Caribbean). This population will make up the majority of the study. However, there are cases of BEN in individuals of Middle Eastern, Caucasian, and other ethnicity. The investigators will accept these patients as they may have unknown African ancestry and genotyping will be important.
  • Age: 18 to 64 years.
  • History of a low absolute neutrophil count (ANC\<2500 cells/mm3 in past 24 months)
  • Documented ability to sign informed consent. This is a score of ≥10/12 on ESC.
  • Effective birth control if of child bearing potential

You may not qualify if:

  • DSM-IV diagnosis of Mental Retardation
  • Pregnancy or lactation
  • History of myeloproliferative disorder
  • Uncontrolled seizure disorder
  • History of paralytic ileus
  • History of clozapine-induced ANC \< 700 mm3
  • Systemic Lupus Erythematosus, Multiple Sclerosis, Hashimoto's Thyroiditis, Sjogren's Syndrome, Grave's Disease\*
  • Medical condition whose pathology or treatment would likely alter the presentation or treatment of schizophrenia or significantly increase the risks associated with the proposed protocol.
  • Medical condition affecting patient's ability to mount an immune response
  • Current bacterial or viral infection\*
  • Sickle cell anemia
  • Positive for bacteria in urine culture\*
  • Temperature \> 37.5 º Celsius, 99.5 º Fahrenheit\*
  • Current treated or untreated cancer\*
  • Documented nutritional deficiencies (such as Beriberi, Pellagra, Rickets, Scurvy, Keshan Disease)\*

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Maryland Psychiatric Research Center

Catonsville, Maryland, 21228, United States

Location

Related Publications (1)

  • Cavaliere VS, Glassman M, DiPaula BA, Mackowick M, Wehring HJ, Liu F, Chen S, Park J, Love RC, Richardson CM, Vyas G, Kearns AM, Kelly DL. Anti-aggressive effects of clozapine in involuntarily committed black patients with severe mental illness. Schizophr Res. 2022 May;243:163-169. doi: 10.1016/j.schres.2022.03.006. Epub 2022 Mar 28.

Related Links

MeSH Terms

Conditions

Schizophrenia

Interventions

Clozapine

Condition Hierarchy (Ancestors)

Schizophrenia Spectrum and Other Psychotic DisordersMental Disorders

Intervention Hierarchy (Ancestors)

DibenzazepinesHeterocyclic Compounds, 3-RingHeterocyclic Compounds, Fused-RingHeterocyclic Compounds

Results Point of Contact

Title
Dr. Deanna L. Kelly, Pharm.D., BCPP
Organization
Maryland Psychiatric Research Center

Study Officials

  • Deanna L Kelly, Pharm.D, BCPP

    Principal Investigator

    PRINCIPAL INVESTIGATOR

Publication Agreements

PI is Sponsor Employee
No
Restrictive Agreement
No

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

February 26, 2015

First Posted

March 31, 2015

Study Start

July 1, 2015

Primary Completion

October 26, 2021

Study Completion

October 26, 2021

Last Updated

January 31, 2023

Results First Posted

January 31, 2023

Record last verified: 2023-01

Locations